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    <script>
        var a = 10;
        ++a;   // a=11 
        var b = ++a + 2;  // 14 
        console.log(b);  //14

        var c = 10;
        c++;   // 11
        var d = c++ + 2 + c;  // 
        console.log(d);  //   

        var e = 10;
        var f = e++ + ++e; 
        console.log(f);  //22
        
    </script>
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